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The diphenylcarbene (DPCs) generated from those precursor diphenyldiazomethane are very persistent, surviving a day in solution at room temperature is reported. The study revealed that CF(sub 3) groups are effective kinetic protector for triplet diphenylcarbenes.

Attempts were made to prepare [2,6-dibromo-4-(3- and 4-pyridyl)phenyl](4-tert-butyl-2,6-dimethylphenyl)diazomethanes and the corresponding carbenes were generated to confirm whether high-spin species can be generated as a result of ferromagnetic interaction between the 3d spin of metal ions and the 2p spins of triplet carbene through the pyridyl group. The 2p spins of triplet carbene can interact magnetically with the 3d spin of metal ions, through the pyridyl group located remote from the carbene center.

Diphenyldazomethanes having phenyl groups at the ortho positions were prepared and the corresponding diphenylcarbenes photolytically generated from them were characterized. The results reveal that triplet carbenes are also trapped by the ortho-phenyl ring to give fluorenes.

The diaryldiazo unit can be connected to an butadiyne unit by an oxidative coupling reaction of acetylene and to the thiophene ring by the Suzuki coupling reaction and the characterization of the bis(carbene) generated from those bis(diazo) compounds is reported. The increase in the lifetime of bis(carbene) indicates that they are thermodynamically stabilized as a result of delocalization of unpaired electrons throughout a pi-net framework.

The photochemical formation of ferrimagnetic chains from a pair of manganese complexes a and b of bis(hexafluoroacetylacetonato)manganese(II) coordinated with diazodi(4-pyridyl)methane in the cis and trans arrangements as repeating units was described. The two isomeric manganese derivatives were prepared individually and were found to have helical and zigzag chain structures. Irradiation of the dilute paramagnetic manganese complexes transformed the diazo groups to the triplet carbenes and formed extended ferrimagnetic chains containing photochemically generated 2p spins.

Experiments were performed to illustrate a systematic synthesis of three trinitroxide radicals displaying quartet ground states. Protection of the hydroxyl group of bis(bromophenyl)-hydroxylamine and the conversion of the nitronyl nitroxide to imino nitroxide by p-toluenesulfonyl isocyanate were performed to synthesize the radicals. The findings revealed the interactions between heterospins and confirmed the quartet ground states of the triradicals.

Research was conducted to examine the Synthesis, structure, and magnetic properties of a cyclic dimer of bis(hexafluoroacetylacetonato)-(1,3-bis(N-tert-butyl-N-oxylamino)-5-tert-bu tyl-benzene)manganese(II). Results indicate that the dimer consists of an alternating cyclic array of two Mn(hfac)2 units and two diradical units. The dimer provides a compound which a cyclic analogue of previously described coordination polymers of similar composition.

A highly efficient, asymmetric synthesis of telcagepant, a CGRP receptor antagonist for the treatment of migraine which features the first application of iminium organocatalysis on an industrial scale is described. The environmentally responsible synthesis is observed to contain all of the elements required for a manufacturing process and prepares telcagepant with the high quality required for pharmaceutical application.

The dianthryldiazomethanes bearing two pyridine groups are described to form complexes with Cu(II) that upon irradiation generate fairly stable high-spin species. Magnetic measurements of the photoproduct using a superconducting quantum interference device magneto are performed to determine the spin state of the complex.

The preparation of a poly(phenyl)-acetylene bearing diazo unit using Rh-complex-catalyzed polymerization and the characterization of poly(carbene) generated from those precursor polydiazo compounds is reported. The observations suggest that a persistent triplet diphenylcarbene unit incorporated into a pi-network of the phenylacetylene polymer in a ferromagnetic fashion indeed acts as a spin source to generate a high-spin ground state.

Steric protection is the ideal method to isolate the triplet carbene with its electronic integrity intact. A series of precursor diphenyldiazomethanes bearing various substituents at the ortho positions as kinetic protectors is prepared.

The preparation of usable high-spin organic materials employing a triplet carbene as a spin source is an achievable objective. The persistent triplet carbenes retain electronic properties and act as a spin source when aligned properly in the pi-electron framework to generate a high-spin molecule.

Research is presented describing a study of N,N,N-tris(p-(N-oxyl-N-tert-butylamino)phenyl)amine, -borane and -methyl. Molecular structure and X-ray crystal analysis of the monoclinic single crystal shows it does not have a zwitterionic quinonoid structure or C3 symmetry.